The instant application should be granted the priority dates of Apr. 22, 2006, the filing date of the corresponding German patent application 10 2006 018 794.6, as well as Apr. 19, 2007, the filing date of the International patent application PCT/DE2007/000692.
The present invention relates to two methods for the placement of a bridge element, an apparatus for the placement of a bridge element as well as a use of this apparatus.
The invention can be used on civilian and military wheeled or chained vehicles for the laying or placement of portable bridges, which generally consist of a plurality of individual bridge elements carried along with the vehicle. For the placement of the bridge elements, which are generally symmetrical in the longitudinal and transverse directions, such vehicles are provided with a pivotable placement arm. Disposed on the placement arm are drive elements that move the bridge elements in the longitudinal direction during the placement. As driving elements, the placement arm is frequently provided in particular with a pair of rail bar gears in the central region of the placement arm that cooperate with two corresponding rail bars on the bridge element and move the latter. As an aid, a further pair of rail bar gears is used that is disposed in the rear region of the placement arm.
The individual bridge elements are generally stacked upon the vehicle. During the placement, the uppermost bridge element is first moved toward the front with the placement arm, being guided in a horizontal plane in the longitudinal direction, so that it projects nearly entirely toward the front of the vehicle. In the event that further bridge elements are to be placed, a second bridge element from the stack is moved toward the front by means of the rail bar gears until it encounters the first bridge element, where the two bridge elements are rigidly coupled with one another. After the coupling, both bridge elements are moved toward the front until also the second bridge element projects nearly entirely toward the front of the vehicle. This process is repeated until the desired number of bridge elements have been coupled. The pivotable placement arm is then pivoted in a vertical plane in such a way that first the front end of the first bridge element is placed upon the ground, and subsequently the rear end of the last bridge element is placed upon the ground.
During the placement, the bridge element must be moved in a controlled manner. In particular, during deposit of the front end the bridge element must not come out of the guide and slip. The error free deposit of the bridge must in particular also be ensured on steep surfaces, for example on a river embankment, and with unfavorable ground conditions (e.g. muddy conditions). Due to the angular conditions that exist, the placement and taking up of only one bridge element is frequently more critical than the placement of a plurality of bridge elements.
The slipping of the bridge can, with the known apparatus, be prevented only by the used of additional auxiliary means. This includes, for example, the installation of chain hoists between the placement device and the bridge element, or between the bridge element and a fixed point in the immediate surroundings. A further possibility is to secure the bridge by using further portable devices such as fork lifts or salvage tanks. The drawback to this, however, is on the one hand high expense and on the other hand that the bridge cannot be entirely placed out of the armored vehicle, thus endangering the safety of personnel, in particular especially during combat.
It is an object of the present invention to prevent an uncontrolled, faulty movement of the bridge element during the placement and the taking-up.